Schoning P, Hamlet M P
Department of Pathology, College of Veterinary Medicine, Kansas State University, Manhattan 66506.
Br J Exp Pathol. 1989 Feb;70(1):41-9.
Frost-bite lesions were produced in five Hanford Miniature Swine exposed to - 75 degrees C air for 1, 3, 5, 10 or 20 min. Biopsies were taken at 0, 3, 6, 12, 24 and 48 h and 1 and 2 weeks. Two hundred slides were evaluated microscopically: pyknosis, vacuolation, individualization of cells, and degeneration were graded from 0-5; 0, no change; 5, severe change. Necrosis, new epithelium, and microabscesses were recorded as present or absent. Early changes of vacuolation of keratinocytes, individualization of cells and pyknosis increased with biopsy time until 1 week, at which time more severe changes predominated. Intermediate changes of advanced degeneration and dermoepidermal microabscesses were seen at 48 h and 1 and 2 weeks. Late changes of necrosis and epithelial regeneration occurred, both separately or together in the same tissue, at 1 and 2 weeks. Regeneration occurred either as complete replacement of epithelium, or as crescents of new epithelium beneath degenerating epithelium. The results show that necrosis is a late development, so prognosis based on early skin biopsies must be guarded to unfavourable. Furthermore, these findings suggest that cold has a direct effect on epithelial cell membranes.
对5只汉福德小型猪进行冻伤损伤实验，将它们暴露于-75摄氏度的空气中1、3、5、10或20分钟。在0、3、6、12、24和48小时以及1周和2周时进行活检。对200张切片进行显微镜评估：核固缩、空泡化、细胞个体化和变性从0到5级进行评分；0表示无变化；5表示严重变化。记录坏死、新上皮形成和微脓肿的有无。角质形成细胞空泡化、细胞个体化和核固缩的早期变化随着活检时间的增加而增加，直到1周，此时更严重的变化占主导。在48小时以及1周和2周时可见晚期变性和真皮表皮微脓肿的中期变化。坏死和上皮再生的晚期变化在1周和2周时出现，可单独出现或在同一组织中同时出现。再生表现为上皮的完全替代，或在变性上皮下方出现新月形的新上皮。结果表明，坏死是晚期发展，因此基于早期皮肤活检的预后必须谨慎判断为不良。此外，这些发现表明寒冷对上皮细胞膜有直接影响。
